Categories who are under hidden categories only (zhwiki_p)

SQL

/* SELECT p.page_title
FROM page p 
INNER JOIN categorylinks cl 
	ON p.page_id = cl.cl_from
LEFT JOIN (
    -- 11k list of hidden categories
	SELECT p2.page_title, pp.pp_propname
	FROM page_props pp 
	INNER JOIN page p2 ON (p2.page_id = pp.pp_page)
	WHERE pp.pp_propname = 'hiddencat'
) hc 
	ON cl.cl_to = hc.page_title
WHERE p.page_namespace = 14 -- 400k
GROUP BY p.page_title
HAVING COUNT(*) = SUM(CASE WHEN hc.pp_propname IS NULL THEN 0 ELSE 1 END)
*/
SELECT page_title, page_latest
FROM page AS pages
WHERE pages.page_namespace = 14
AND pages.page_is_redirect = 0
AND NOT EXISTS (
  SELECT 1 FROM categorylinks
  LEFT JOIN page AS categories ON categories.page_title = cl_to AND categories.page_namespace = 14
  LEFT JOIN page_props ON pp_page = categories.page_id AND pp_propname = 'hiddencat'
  WHERE cl_from = pages.page_id AND (pp_propname IS NULL OR categories.page_title IS NULL)
) ORDER BY page_title
SQL

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